-LRB- CNN -RRB- -- The president of Ukraine 's top football club has warned six of its players who have gone AWOL they will `` suffer '' if they do n't return to the conflict-torn country .

Shakhtar Donetsk had played a friendly against Lyon on Saturday , but after the game five Brazilians and one Argentine remained in France rather than travel back to Ukraine . On Monday there was fighting in the eastern Ukrainian city of Donetsk .

`` I do n't rule out that these players will return to the team quickly , and some of them -- tomorrow , '' Shakhtar president Rinat Akhmetov told the club 's official website .

`` Players have contracts that they have to abide by . If they do not come , I think , they will be the first to suffer . Each of them has a minimum release clause , which is tens of millions of euros .

`` If someone wants to reduce this amount by a million , then such a decision is our right . ''

Akhmetov also assured Brazilians Douglas Costa , Fred , Dentinho , Alex Teixiera , Ismaily and Facundo Ferreyra of Argentina they have `` nothing to fear '' if and when they return to Ukraine .

`` Hopefully , the mind and heart will prevail over misunderstanding , and the players will not follow temptation and fear , '' said the Shakhtar president .

`` We are ready to provide security . We will not take risks and in any case we wo n't bring players to dangerous places . ''

Shakhtar , which regularly features in Europe 's top competition the Champions League , play rivals Dynamo Kiev in the Ukrainian Super Cup Tuesday , a curtain raiser to the Ukraine domestic league season .

`` Despite the fact that we will be weakened in the Super Cup match against Dynamo Kyiv , our players will do their best to make the game hard for our opponents , '' added Akhmetov .

The ongoing unrest in the region means Shakhtar , the reigning Ukrainian champion , is unable to play matches at its Donbass Arena stadium .

The Ukrainian football season is due to start this weekend , with Shakhtar scheduled to host Metalurh Zaporizhya .

It is unclear where the match will be played , although Akhmetov would like it to take place in Kharkiv , a city over 150 miles north of Donetsk .

`` We want to play in Donetsk very much , but , unfortunately , at the moment we can not do it .

`` The decision regarding the championship is taken by the Ukrainian Football Federation . Through our game , we will call for peace and try to bring joy to our fans . ''

Of the six AWOL players , playmaker Douglas Costa is arguably the most valuable .

The 23-year-old has previously been linked with Manchester United , but Akhmetov ruled out a `` clearance sale . ''

Prior to the Malaysia Airlines Flight 17 crash last weeks , European governing body UEFA 's Emergency Panel decided its European club competition matches involving Ukrainian clubs would be allowed to take place in Dnipropetrovsk and Odessa , in addition to Kiev and Lviv .

Dnipro Dnipropetrovsk will play in the third qualifying round of the UEFA Champions League while Chornomorets Odessa are in the Europa League .

UEFA 's Emergency Panel also ruled Ukrainian and Russian teams can not be drawn against each other in its competitions .

That ensured Dnipro were not drawn against Russian club Zenit St Petersburg when the UEFA Champions League third qualifying round draw was made last week .

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Six Shakhtar Donetsk players refuse to return to Ukraine after playing against Lyon

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Five Brazilians and one Argentine remained in France

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Shakhtar is unable to play matches at its Donbass Arena stadium